Have been having issues with clock resetting itself and failing to keep time whilst ignition on so decided to replace both main and aux batteries.I have an E class estate 320 cdi built June 2007.
Looked under the bonnet, removed filter box on Right hand side but there is no battery there. Have attached photo.

Do all models have a consumer battery? if so where else should I look?
Graham

 

2007 and later did not have auxiliary batteries.

 

Thanks for quick reply.!